Sealing structures for paravalvular leak protection

ABSTRACT

A prosthetic heart valve for replacing a native valve includes a collapsible and expandable stent having a proximal end and a distal end, and a valve assembly disposed within the stent, the valve assembly including a plurality of leaflets and a cuff annularly disposed about the stent. The cuff includes a surplus portion capable of forming a sealing structure having a diameter greater than a diameter of the proximal end of the stent when deployed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.14/547,595, filed on Nov. 19, 2014, which claims the benefit of thefiling date of U.S. Provisional Patent Application No. 61/906,076, filedon Nov. 19, 2013, the disclosures of which are hereby incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present disclosure relates in general to heart valve replacementand, in particular, to collapsible prosthetic heart valves. Moreparticularly, the present disclosure relates to devices and methods forpositioning and sealing collapsible prosthetic heart valves within anative valve annulus.

Prosthetic heart valves that are collapsible to a relatively smallcircumferential size can be delivered into a patient less invasivelythan valves that are not collapsible. For example, a collapsible valvemay be delivered into a patient via a tube-like delivery apparatus suchas a catheter, a trocar, a laparoscopic instrument, or the like. Thiscollapsibility can avoid the need for a more invasive procedure such asfull open-chest, open-heart surgery.

Collapsible prosthetic heart valves typically take the form of a valvestructure mounted on a stent. There are two common types of stents onwhich the valve structures are ordinarily mounted: a self-expandingstent or a balloon-expandable stent. To place such valves into adelivery apparatus and ultimately into a patient, the valve must firstbe collapsed or crimped to reduce its circumferential size.

When a collapsed prosthetic valve has reached the desired implant sitein the patient (e.g., at or near the annulus of the patient's heartvalve that is to be replaced by the prosthetic valve), the prostheticvalve can be deployed or released from the delivery apparatus andre-expanded to full operating size. For balloon-expandable valves, thisgenerally involves releasing the entire valve, and then expanding aballoon positioned within the valve stent. For self-expanding valves, onthe other hand, the stent automatically expands as the sheath coveringthe valve is withdrawn.

SUMMARY OF THE INVENTION

In some embodiments, a prosthetic heart valve for replacing a nativevalve includes a collapsible and expandable stent having a proximal endand a distal end and a valve assembly disposed within the stent, thevalve assembly including a plurality of leaflets. The heart valvefurther includes a cuff annularly disposed about the stent and having asurplus portion capable of forming a sealing structure at the proximalend of the stent, the sealing structure having a deployed condition witha diameter in the deployed condition greater than a diameter of theproximal end of the stent.

In some embodiments, a prosthetic heart valve for replacing a nativevalve includes a collapsible and expandable stent having a proximal endand a distal end, a valve assembly disposed within the stent, the valveassembly including a plurality of leaflets and a cuff annularly disposedabout the stent and having an attached end coupled to the stent and afree end extending past the proximal end of the strut and capable offorming a sealing structure for sealing gaps between the prostheticheart valve and a native valve annulus.

In some embodiments, a method of making a prosthetic heart valve forreplacing a native valve includes providing a collapsible and expandablestent having a proximal end and a distal end, coupling a valve assemblyto the stent, the valve assembly including a plurality of leaflets,coupling a cuff to the stent so that a surplus portion of the cuffextends beyond the proximal end of the strut and converting the surplusportion of the cuff into a sealing structure at the proximal end of thestent, the sealing structure having a diameter greater than a diameterof the proximal end of the stent.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present invention will now be described withreference to the appended drawings. It is to be appreciated that thesedrawings depict only some embodiments of the invention and are thereforenot to be considered limiting of its scope.

FIG. 1 is a side elevational view of a conventional prosthetic heartvalve;

FIG. 2A is a highly schematic cross-sectional view taken along line A-Aof FIG. 1 and showing the prosthetic heart valve disposed within anative valve annulus;

FIG. 2B is a highly schematic cross-sectional view showing a prostheticmitral valve disposed within a native valve annulus;

FIGS. 3A and 3B are highly schematic side views of one embodiment of aheart valve having a sealing portion intended to fill irregularitiesbetween the heart valve and the native valve annulus;

FIGS. 4A-E are highly schematic side views of one method of deliveringand deploying the heart valve of FIGS. 3A and 3B within the native valveannulus;

FIGS. 5A and 5B are enlarged highly schematic partial side views ofanother embodiment of a heart valve having a sealing portion disposed atthe annulus section;

FIG. 5C is an enlarged highly schematic partial side view of anotherembodiment of a heart valve showing attachment ends of the elongatedlegs coupled to struts of a stent;

FIGS. 6A and 6B are enlarged highly schematic partial side views ofanother embodiment of a heart valve having multiple sealing portions;

FIG. 7A is an enlarged highly schematic partial side view of anotherembodiment of a heart valve having elongated legs with multiple eyelets;

FIG. 7B is an enlarged highly schematic partial side view of anotherembodiment of a heart valve having wavy legs;

FIGS. 7C and 7D are enlarged highly schematic partial side views ofanother embodiment of a heart valve having pairs of elongated legs inthe extended and relaxed configurations, respectively;

FIGS. 8A-C are highly schematic side views of heart valves havingsealing rings disposed at various locations relative to the nativeleaflets;

FIGS. 9A and 9B are enlarged highly schematic partial side views ofanother embodiment of a heart valve having elongated legs in theextended and relaxed configurations, respectively;

FIGS. 9C and 9D are examples of the shortening of an elongated leg fromthe extended configuration of FIG. 9A to the relaxed configuration ofFIG. 9B;

FIGS. 10A and 10B are highly schematic side views of another embodimentof a heart valve having a sealing ring intended to fill irregularitiesbetween the heart valve and the native valve annulus;

FIGS. 10C-E are highly schematic partial side views of elongated legs ina stretched configuration and two variations of bending the elongatedlegs;

FIG. 10F is an enlarged partial perspective view of the bending of theelongated legs;

FIGS. 11A-F are highly schematic partial side views of a heart valveshowing variations of bending the elongated legs;

FIG. 12 is a highly schematic cross-sectional view showing a prostheticheart valve disposed within a native valve annulus and having a sealingring in its fully expanded state;

FIGS. 13A and 13B are highly schematic side views of another embodimentof a heart valve having a sealing ring intended to fill irregularitiesbetween the heart valve and the native valve annulus;

FIG. 13C is a schematic end view of the prosthetic heart valve of FIGS.13A and 13B after formation of a sealing ring as seen from the annulusend toward the aortic end of the heart valve;

FIGS. 13D is a highly schematic side view of a variation of theembodiment shown in FIGS. 13A-C;

FIG. 14A is a highly schematic side view of another embodiment of aheart valve having an undulating sealing ring intended to fillirregularities between the heart valve and the native valve annulus;

FIG. 14B is a schematic end view of the prosthetic heart valve of FIG.14A after formation of an undulating sealing ring as seen from theannulus end toward the aortic end of the heart valve;

FIG. 15A is a highly schematic side view of another embodiment of aheart valve having a halo sealing ring intended to fill irregularitiesbetween the heart valve and the native valve annulus;

FIG. 15B is a schematic end view of the prosthetic heart valve of FIG.15A after formation of the halo sealing ring as seen from the annulusend toward the aortic end of the heart valve;

FIG. 16A is a highly schematic side view of another embodiment of aheart valve having a sealing body with limbs intended to fillirregularities between the heart valve and the native valve annulus; and

FIG. 16B is a schematic end view of the prosthetic heart valve of FIG.16A after formation of the sealing body as seen from the annulus endtoward the aortic end of the heart valve.

DETAILED DESCRIPTION

Despite the various improvements that have been made to the collapsibleprosthetic heart valve delivery process, conventional devices sufferfrom some shortcomings. For example, with conventional self expandingvalves, clinical success of the valve is dependent on accuratedeployment and anchoring. Inaccurate deployment and anchoring of thevalve increases risks, such as those associated with valve migration,which may cause severe complications and possibly death due to theobstruction of the left ventricular outflow tract. Inaccurate deploymentand anchoring may also result in the leakage of blood between theimplanted heart valve and the native valve annulus, commonly referred toas perivalvular leakage (also known as “paravalvular leakage”). Inaortic valves, this leakage enables blood to flow from the aorta backinto the left ventricle, reducing cardiac efficiency and putting agreater strain on the heart muscle. Additionally, calcification of theaortic valve may affect performance and the interaction between theimplanted valve and the calcified tissue is believed to be relevant toleakage, as will be outlined below.

Moreover, anatomical variations from one patient to another may cause afully deployed heart valve to function improperly, requiring removal ofthe valve from the patient. Removing a fully deployed heart valveincreases the length of the procedure as well as the risk of infectionand/or damage to heart tissue. Thus, methods and devices are desirablethat would reduce the need to remove a prosthetic heart valve from apatient. Methods and devices are also desirable that would reduce thelikelihood of perivalvular leakage due to gaps between the implantedheart valve and patient tissue.

There therefore is a need for further improvements to the devices,systems, and methods for transcatheter delivery and positioning ofcollapsible prosthetic heart valves. Specifically, there is a need forfurther improvements to the devices, systems, and methods for accuratelyimplanting a prosthetic heart valve. Among other advantages, the presentdisclosure may address one or more of these needs.

As used herein, the term “proximal,” when used in connection with aprosthetic heart valve, refers to the end of the heart valve closest tothe heart when the heart valve is implanted in a patient, whereas theterm “distal,” when used in connection with a prosthetic heart valve,refers to the end of the heart valve farthest from the heart when theheart valve is implanted in a patient. When used in connection withdevices for delivering a prosthetic heart valve or other medical deviceinto a patient, the terms “trailing” and “leading” are to be taken asrelative to the user of the delivery devices. “Trailing” is to beunderstood as relatively close to the user, and “leading” is to beunderstood as relatively farther away from the user. Also as usedherein, the terms “generally,” “substantially,” and “about” are intendedto mean that slight deviations from absolute are included within thescope of the term so modified.

The sealing portions of the present disclosure may be used in connectionwith collapsible prosthetic heart valves. FIG. 1 shows one suchcollapsible stent-supported prosthetic heart valve 100 including a stent102 and a valve assembly 104 as is known in the art. The prostheticheart valve 100 is designed to replace a native tricuspid valve of apatient, such as a native aortic valve. It should be noted that whilethe inventions herein are described predominantly in connection withtheir use with a prosthetic aortic valve and a stent having a shape asillustrated in FIG. 1, the valve could be a bicuspid valve, such as themitral valve, and the stent could have different shapes, such as aflared or conical annulus section, a less-bulbous aortic section, andthe like, and a differently shaped transition section.

Prosthetic heart valve 100 will be described in more detail withreference to FIG. 1. Prosthetic heart valve 100 includes expandablestent 102 which may be formed from biocompatible materials that arecapable of self-expansion, such as, for example, shape memory alloys,such as the nickel-titanium alloy known as “Nitinol” or other suitablemetals or polymers. Stent 102 extends from a proximal or annulus end 130to a distal or aortic end 132, and includes annulus section 140 adjacentproximal end 130, transition section 141 and aortic section 142 adjacentdistal end 132. Annulus section 140 has a relatively small cross-sectionin the expanded condition, while aortic section 142 has a relativelylarge cross-section in the expanded condition. Preferably, annulussection 140 is in the form of a cylinder having a substantially constantdiameter along its length. Transition section 141 may taper outwardlyfrom annulus section 140 to aortic section 142. Each of the sections ofstent 102 includes a plurality of struts 160 forming cells 162 connectedto one another in one or more annular rows around the stent. Forexample, as shown in FIG. 1, annulus section 140 may have two annularrows of complete cells 162 and aortic section 142 and transition section141 may each have one or more annular rows of partial cells 162. Cells162 in aortic section 142 may be larger than cells 162 in annulussection 140. The larger cells in aortic section 142 better enableprosthetic valve 100 to be positioned in the native valve annuluswithout the stent structure interfering with blood flow to the coronaryarteries.

Stent 102 may include one or more retaining elements 168 at distal end132 thereof, retaining elements 168 being sized and shaped to cooperatewith female retaining structures (not shown) provided on the deploymentdevice. The engagement of retaining elements 168 with the femaleretaining structures on the deployment device helps maintain prostheticheart valve 100 in assembled relationship with the deployment device,minimizes longitudinal movement of the prosthetic heart valve relativeto the deployment device during unsheathing or resheathing procedures,and helps prevent rotation of the prosthetic heart valve relative to thedeployment device as the deployment device is advanced to the targetlocation and the heart valve deployed.

Prosthetic heart valve 100 includes valve assembly 104 preferablypositioned in annulus section 140 of the stent 102 and secured to thestent. Valve assembly 104 includes cuff 176 and a plurality of leaflets178 which collectively function as a one-way valve by coapting with oneanother. As a prosthetic aortic valve, valve 100 has three leaflets 178.However, it will be appreciated that other prosthetic heart valves withwhich the sealing portions of the present disclosure may be used mayhave a greater or lesser number of leaflets 178.

Although cuff 176 is shown in FIG. 1 as being disposed on the luminal orinner surface of annulus section 140, it is contemplated that cuff 176may be disposed on the abluminal or outer surface of annulus section 140or may cover all or part of either or both of the luminal and abluminalsurfaces. Both cuff 176 and leaflets 178 may be wholly or partly formedof any suitable biological material or polymer such as, for example,polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), ultra-highmolecular weight polyethylene, silicone, urethane and the like.

Leaflets 178 may be attached along their belly portions to cells 162 ofstent 102, with the commissure between adjacent leaflets 178 attached tocommissure features 166. As can be seen in FIG. 1, each commissurefeature 166 may lie at the intersection of four cells 162, two of thecells being adjacent one another in the same annular row, and the othertwo cells being in different annular rows and lying in end-to-endrelationship. Preferably, commissure features 166 are positionedentirely within annulus section 140 or at the juncture of annulussection 140 and transition section 141. Commissure features 166 mayinclude one or more eyelets which facilitate the suturing of the leafletcommissure to stent 102.

Prosthetic heart valve 100 may be used to replace a native aortic valve,a surgical heart valve or a heart valve that has undergone a surgicalprocedure. Prosthetic heart valve 100 may be delivered to the desiredsite (e.g., near the native aortic annulus) using any suitable deliverydevice. During delivery, prosthetic heart valve 100 is disposed insidethe delivery device in the collapsed condition. The delivery device maybe introduced into a patient using a transfemoral, transapical,transseptal, transradial, transsubclavian, transaortic or any otherpercutaneous approach. Once the delivery device has reached the targetsite, the user may deploy prosthetic heart valve 100. Upon deployment,prosthetic heart valve 100 expands so that annulus section 140 is insecure engagement within the native aortic annulus. When prostheticheart valve 100 is properly positioned inside the heart, it works as aone-way valve, allowing blood to flow from the left ventricle of theheart to the aorta, and preventing blood from flowing in the oppositedirection.

Problems may be encountered when implanting prosthetic heart valve 100.For example, in certain procedures, collapsible valves may be implantedin a native valve annulus without first resecting the native valveleaflets. The collapsible valves may have critical clinical issuesbecause of the nature of the stenotic leaflets that are left in place.Additionally, patients with uneven calcification, bi-cuspid aortic valvedisease, and/or valve insufficiency cannot be treated well, if at all,with the current collapsible valve designs.

The reliance on unevenly calcified leaflets for proper valve placementand seating could lead to several problems, such as perivalvular leakage(PV leak), which can have severe adverse clinical outcomes. To reducethese adverse events, the optimal valve would anchor adequately and sealwithout the need for excessive radial force that could harm nearbyanatomy and physiology.

FIG. 2A is a highly schematic cross-sectional illustration of aprosthetic aortic valve 100A disposed within native valve annulus 250A.As seen in the figure, valve assembly 104A has a substantially circularcross-section which is disposed within the non-circular native valveannulus 250A. At certain locations around the perimeter of heart valve100A, gaps 200A form between heart valve 100A and native valve annulus250A. Blood flowing through these gaps and past valve assembly 104A ofprosthetic heart valve 100A can cause regurgitation and otherinefficiencies which reduce cardiac performance. Such improper fitmentmay be due to suboptimal native valve annulus geometry due, for example,to calcification of native valve annulus 250A or to unresected nativeleaflets.

FIG. 2B is a similar cross-sectional illustration of a prosthetic mitralvalve 100B disposed within native valve annulus 250B. As seen in thefigure, valve assembly 104B has a substantially D-shaped cross-sectionwhich is disposed within irregularly-shaped annulus 250B. At certainlocations around the perimeter of heart valve 100B, gaps 200B formbetween heart valve 100B and native valve annulus 250B. Regurgitationand other inefficiencies may thus result in a prosthetic mitral valve.Though the following examples show aortic valves, it will be understoodthat the present devices and methods may be equally applicable to mitralheart valves.

FIGS. 3A and 3B illustrate one embodiment of heart valve 300 intended tofill the irregularities between the heart valve and native valve annulus250A shown in FIG. 2A. Heart valve 300 extends between proximal end 302and distal end 304, and may generally include stent 306 and valveassembly 308 having a plurality of leaflets 310 and cuff 312. Heartvalve 300 may be formed of any of the materials and in any of theconfigurations described above with reference to FIG. 1.

Additionally, heart valve 300 may include a number of elongated legs 320and a sealing portion 322 coupled to the elongated legs via eyelets 324to mitigate perivalvular leakage. Attachment ends 325 of elongated legs320 may be affixed to stent 306 near the proximal end 302 of heart valve300, and legs 320 may extend away from the distal end 304 of stent 306and terminate at free ends 326, which are unattached and free to move.As will be shown in subsequent examples, elongated legs 320 may insteadbe oriented in the opposition direction, being affixed near the proximalend 302 of heart valve 300 and extending toward the distal end 304 ofthe heart valve. Attachment ends 325 of elongated legs 320 may beaffixed to stent 306 using welding, adhesive, or any other suitabletechnique known in the art. Additionally, legs 320 may be formed of ashape memory material such as those described above for forming stent102 of FIG. 1, and may have an extended configuration and a relaxedconfiguration. In the extended configuration, shown in FIG. 3A,elongated legs 320 may be substantially linear. Moreover, instead ofbeing separately formed and affixed to stent 306 at attachment ends 325,elongated legs 320 may be integrally formed with stent 306, such as bylaser cutting both stent 306 and elongated legs 320 from the same tube.

Sealing portion 322 may be attached to legs 320 to form a cylindricaltube around the interior or exterior of the legs. Sealing portion 322may be attached to legs 320 via sutures, adhesive or any other suitablemethod. For example, each leg 320 may include eyelets 324 and sealingportion 322 may be attached to eyelets 324 via sutures (not shown).Where eyelets 324 are provided in this or any of the other embodimentsdescribed herein, they may be disposed at the free ends of legs 320 asillustrated in FIG. 3A, or anywhere else along the length of the legs.Providing eyelets 324 along the length of legs 320 may better holdsealing portion 322 to the legs as the legs move between their extendedand relaxed configurations. Moreover, it will be understood that otherfeatures such as indentations or notches may be used to couple twoportions of the prosthetic valve using sutures.

Sealing portion 322 may be formed of the same material as cuff 312,including natural materials such as, for example, bovine or porcinepericardium, or synthetic materials such as, for example,ultra-high-molecular-weight polyethylene (UHMWPE), or combinationsthereof. In one example, sealing portion 322 may be formed by increasingthe length of cuff 312 and extending it over the proximal end 302 andlegs 320 of heart valve 300. Alternatively, sealing portion 322 may beformed separately from cuff 312 and attached to eyelets 324 at theproximal end 302 of heart valve 300 to form a seam with cuff 312.

In a variant of the foregoing, sealing portion 322 of heart valve 300may be formed from a tubular section of braided fabric comprising aplurality of braided strands. The strands forming the braid may have apredetermined relative orientation with respect to one another (e.g., ahelical braid). Moreover, sealing portion 322 may comprise a pluralityof layers of braided fabric and/or other occluding material such thatsealing portion 322 is capable of at least partially inhibiting bloodflow therethrough in order to promote the formation of thrombus,endothelialization and epithelialization.

In such variants, sealing portion 322 may be formed of a passivematerial (e.g., one that does not change shape in response to astimulus) so that it simply conforms to the shape of legs 320.Alternatively, sealing portion 322 may be formed, for example, of abraided fabric mesh of a shape-memory material, of a super-elasticmaterial, of a bio-compatible polymer, or of another material that iscapable of being actuated between an extended configuration and arelaxed configuration. Sealing portion 322 may comprise a braided metalfabric that is both resilient and capable of heat treatment tosubstantially set a desired shape (e.g., the relaxed configuration shownin FIG. 3B). One class of materials which meets these qualifications isshape memory alloys, such as Nitinol. It is also understood that sealingportion 322 may comprise various materials other than Nitinol that haveelastic and/or memory properties, such as spring stainless steel, tradenamed alloys such as Elgiloy®, and Hastelloy®, CoCrNi alloys (e.g.,trade name Phynox), MP35N®, CoCrMo alloys, mixtures of such alloys ormixtures of metal and polymer fibers. Depending on the individualmaterial selected, the strand diameter, number of strands, and pitch maybe altered to achieve the desired properties for sealing portion 322.Thus, sealing portion 322 may alternate between the extendedconfiguration and the relaxed configuration due to the changing shape oflegs 320 or alternatively it may itself alternate between the twoconfigurations due to its own shape-memory material properties.

FIG. 3B illustrates the relaxed configuration of heart valve 300. Asnoted above, legs 320 may have an extended configuration and a relaxedconfiguration. To effectuate this change in configuration, legs 320 maybe curled and subjected to a heat setting process. This process may beaccomplished in a series of steps. For example, legs 320 may be formedwith a first curl and heat set, and then formed with a second curl andfurther heat set. The relaxed configuration of legs 320 may thereforeinclude multiple curls due to the curling and heat setting processdescribed above. Legs 320 may be straightened to the extendedconfiguration (shown in FIG. 3A and described above) for cooperationwith a delivery system as will be described below with reference toFIGS. 4A-E, and may return to the curled, relaxed configuration afterremoval from the delivery system. As shown in FIG. 3B, when heart valve300 is permitted to return to its relaxed configuration, legs 320 maycurl up toward distal end 304 and pull sealing portion 322 with them,rolling sealing portion 322 up in the process to form sealing ring 350at proximal end 302 of heart valve 300. Sealing ring 350 may have aradius larger than that of valve assembly 308, the larger radius ofsealing ring 350 being capable of filling any gaps between heart valve300 and the native valve annulus (not shown). The length of sealing ring350 may depend on the number of curls of legs 320. For example, sealingring 350 may have a length that is approximately one-half of the lengthof legs 320. As shown in FIG. 3B, sealing ring 350 is formed belowproximal end 302 and may be suitable for a sub-leaflet application aswill be described in greater detail below with reference to FIGS. 8A-8C.Sealing ring 350 may be readily deformable to conform to the shape ofthe native valve annulus, portions of sealing ring 350 being configuredto compress when pressed against the walls of the native valve annulusand other portions of sealing ring 350 being configured to radiallyexpand in gaps, thereby filling the gaps between heart valve 300 and thenative valve annulus.

A method of delivering and implanting heart valve 300 will now bedescribed with reference to FIGS. 4A-E. A delivery system 400 may beused to deliver and deploy heart valve 300 in native valve annulus 250A,and may generally include sheath 410, core 420, atraumatic tip 430 andhub 440. Sheath 410 may be slidable relative to core 420. Heart valve300, including stent 306, valve assembly 308, legs 320 and sealingportion 322, may be disposed within sheath 410 about core 420 (FIG. 4A).Hub 440 may be coupled to core 420 and configured to mate with retainingelements 360 of heart valve 300. Elongated legs 320 of heart valve 300may be disposed in the extended configuration of FIG. 3A, substantiallyparallel to sheath 410, during delivery. Specifically, though legs 320are configured to return to their relaxed configuration by curlingoutwardly, they may be kept substantially linear by being constrainedwithin sheath 410. By doing so, sealing portion 322 and legs 320 may bedelivered to the native valve annulus using delivery system 400 withoutincreasing the radius of sheath 410, avoiding the need to increase thecrimp profile of the heart valve within delivery system 400. A largedelivery system may be incapable of being passed through the patient'svasculature, while a delivery system having a heart valve with a smallercrimp profile may be easier to navigate through the patient's body andmay also reduce the operation time. In the example shown in FIGS. 4A-E,delivery system 400 is delivered from the aorta toward the leftventricle as indicated by arrow 51. If heart valve 300 or deliverysystem 400 includes echogenic materials, such materials may be used toguide delivery system 400 to the appropriate position using theassistance of three-dimensional echocaradiography to visualize heartvalve 300 within the patient. Alternative visualization techniques knownin the art are also contemplated herein.

When delivery system 400 has reached the proper location (e.g.atraumatic tip 430 is just past native valve annulus 250A), atraumatictip 430 may be advanced slightly in the direction of arrow S1 toward theleft ventricle by pushing core 420 toward atraumatic tip 430 whileholding sheath 410 in place which serves to decouple atraumatic tip 430from sheath 410 (FIG. 4B). Sheath 410 may then be retracted in thedirection of arrow S2 toward the aorta. As seen in FIG. 4B, with sheath410 slightly retracted, legs 320 begin to emerge from the sheath andreturn to their relaxed configuration by curling outwardly with sealingportion 322, which is attached thereto, curling along with legs 320. Assheath 410 is further retracted in the direction of arrow S2, more ofeach leg 320 is exposed and curls upon itself (FIG. 4C) until legs 320fully return to their relaxed configuration (FIG. 4D). Sealing portion322 attached to curled legs 320 forms sealing ring 350. At thisjuncture, stent 306 is still disposed within sheath 410 and heart valve300 has not yet begun to expand. Sheath 410 may be retracted furtheruntil heart valve 300 is free to self-expand within native valve annulus250A. While heart valve 300 is partially deployed (e.g., a portion ofheart valve 300 is outside sheath 410, but heart valve 300 is not fullydetached from delivery system 400), if it appears that heart valve 300needs to be recaptured and redeployed due to, for example, improperpositioning or orientation, sheath 410 may be slid over core 420 in thedirection of arrow S1 to recapture heart valve 300 within sheath 410.During recapture, sheath 410 may push against legs 320 to straightenthem to the extended configuration shown in FIG. 4A. This process may berepeated until heart valve 300 is properly positioned and deployedwithin native valve annulus 250A. After sheath 410 has been fullyretracted to expose heart valve 300, sealing ring 350, being disposed atproximal end 302 of heart valve 300, may occlude gaps 200 between heartvalve 300 and native valve annulus 250A, thereby reducing or eliminatingthe amount of blood that passes around heart valve 300 through gaps 200(FIG. 4E). Retaining elements 360 of heart valve 300 may be decoupledfrom hub 440 and delivery system 400, including atraumatic tip 430, maythen be retracted through heart valve 300 in the direction of arrow S2and removed from the patient.

FIGS. 5A and 5B are enlarged schematic partial side views showing heartvalve 500 having legs in an extended configuration and in a relaxedconfiguration, respectively. Heart valve 500 extends between proximalend 502 and a distal end (not shown) and generally includes stent 506and a valve assembly (not shown for the sake of clarity) having a cuffand leaflets similar to those described above with reference to FIGS. 3Aand 3B. Heart valve 500 further includes elongated legs 520 and sealingportion 522 attached to elongated legs 520 at eyelets 524 via sutures.These elements may be formed of any of the materials described abovewith reference to FIGS. 3A and 3B. Legs 520 may be attached to or formedintegrally with stent 506 at attachment ends 525 to couple legs 520 tostent 506. As seen in FIG. 5A, legs 520 may be attached to stent 506 ateyelets 524 near the proximal end 502 of heart valve 500 at the top ofthe second row of cells 542 of stent 506, and in their extendedconfiguration, may extend substantially linearly toward the distal endof the valve, terminating at free ends 526.

FIG. 5B illustrates the relaxed configuration of legs 520. Legs 520 maybe biased so that, when they return to their relaxed configuration, theycurl down toward the proximal end 502 of the valve. Due to the couplingof sealing portion 522 to legs 520, the curling of legs 520 results in asimilar curling of sealing portion 522, causing it to roll down in theprocess to form upper sealing ring 550 within annulus portion 540 ofheart valve 500. Upper sealing ring 550 may have a radius larger thanthat of the valve assembly, and therefore may be capable of filling anygaps between heart valve 500 and the native valve annulus (not shown).As shown in FIG. 5B, sealing ring 550 is spaced from proximal end 502and may be useful for intra-leaflet applications that are describedbelow with reference to FIG. 8A-C. In at least some examples, sealingring 550 may be positioned within annulus portion 540 so as to bedirectly radially outward of the leaflets of heart valve 500 (notshown). Heart valve 500 may be disposed within a delivery system,delivered to the native valve annulus and deployed therein using adelivery system that is the same as or similar to that described inFIGS. 4A-E.

Alternatively, legs 520 may be attached to stent 506 at eyelets 524 and,in the extended condition, may extend substantially linearly toward theproximal end 502 of heart valve 500 so that free ends 526 are closer toproximal end 502 than attachment ends 525. In this alternative example,legs 520 may curl upward toward the distal end to form sealing ring 550.Thus, the location of attachment ends 525 and the direction of thecurling of legs 520 may be used to vary the position of sealing ring 550with respect to heart valve 500.

FIG. 5C is an enlarged schematic partial side view showing an alternateextended configuration of the elongated legs. Heart valve 500C extendsbetween a proximal end 502C and a distal end (not shown) and generallyincludes stent 506C and a valve assembly (not shown for the sake ofclarity) having a cuff and leaflets similar to those described abovewith reference to FIGS. 3A and 3B. Heart valve 500C further includeselongated legs 520C and sealing portion 522C attached to elongated legs520C. These elements may be formed of any of the materials describedabove with reference to FIGS. 3A and 3B. Legs 520C may be attached to orformed integrally with stent 506C at attachment ends 525C to couple legs520C to stent 506C. Specifically, legs 520C may be coupled to one ormore struts 541C forming cells 542C or a portion of a cell. Though theprevious embodiments have shown attachment ends 525C as being attachedto or originating from an intersection of two struts 541C, attachmentends 525C may be coupled to or formed integrally with only one strut541C. In this example, four struts 541C forming the four sides of cell542C intersect at four corners of the cell, and attachment ends 525C arecoupled to a single strut 541C approximately halfway between two cornersof the cell. It will be understood, however, that elongated legs 520Cmay be coupled to any portion of stent 506C and/or to any location alongstruts 541C and/or to any number of struts. Elongated legs 520C may curlfrom a relaxed configuration in the same manners described above inconnection with FIGS. 5A and 5B to form a sealing ring.

FIGS. 6A and 6B are schematic side views of another embodiment, showingheart valve 600 having legs in an extended configuration and a relaxedconfiguration, respectively. Heart valve 600 extends between proximalend 602 and a distal end (not shown) and generally includes stent 606and a valve assembly (not shown for the sake of clarity) having a cuffand leaflets similar to those described above with reference to FIGS. 3Aand 3B. Heart valve 600 further includes first elongated legs 620 andfirst sealing portion 622, which may be attached to first elongated legs620 at eyelets 624 via sutures. In a configuration similar to thatdescribed above with reference to FIGS. 5A and 5B, first legs 620 may beattached to or formed integrally with stent 606 at attachment ends 625near the proximal end 602 of heart valve 600, and may extendsubstantially linearly toward the distal end of the valve, terminatingat free ends 626. Heart valve 600 further includes second elongated legs680 attached to stent 606 at second attachment ends 685, which arelocated at proximal end 602 of the valve, and, in the extendedcondition, legs 680 extend substantially linearly away from the distalend of the valve to terminate at second free ends 686 beyond proximalend 602 of heart valve 600. A second sealing portion 682, similar to thesealing portion described above in connection with FIGS. 3A and 3B, maybe attached to legs 680.

FIG. 6B illustrates the relaxed configuration of the legs of heart valve600. First legs 620 may be biased so that, when they return to theirrelaxed configuration, they curl down toward the proximal end 602 of thevalve, as shown in FIG. 6B. Due to the coupling of first sealing portion622 to first legs 620, the curling of first legs 620 results in asimilar curling of first sealing portion 622, causing it to roll down inthe process to form upper sealing ring 650 within annulus portion 640 ofheart valve 600 (e.g. forming a ring at an intra-leaflet position).Likewise, when secondary legs 680 return to their relaxed configuration,they may curl up toward the distal end of heart valve 600, pullingsecond sealing portion 682 with them to form lower sealing ring 690(e.g., forming a ring at a sub-leaflet position). When heart valve 600is implanted using a delivery system similar to that shown in FIGS.4A-E, lower sealing ring 690 may take shape first as the outer sheath ofthe delivery system is retracted, followed by upper sealing ring 650.Additional methods may be used to actuate the formation of either of thesealing rings regardless of the delivery approach.

FIGS. 7A-D illustrate several additional variants of a heart valvehaving sealing portions according to the present disclosure. In FIG. 7A,heart valve 700A extends between proximal end 702 and a distal end (notshown) and generally includes stent 706 and a valve assembly (not shown)having a cuff and leaflets. Heart valve 700A further includes elongatedlegs 720 coupled to stent 706 near proximal end 702, which legs 720, intheir extended configuration, may extend substantially linearly awayfrom the distal end of the valve. A sealing portion 722 is coupled tolegs 720. In order to provide a more secure attachment of sealingportion 722 to legs 720, each leg 720 may include multiple eyelets724A-D along its length, and sealing portion 722 may be coupled to legs720 at each of the eyelets. Eyelets 724A-D may be uniformly distributedalong the length of each leg 720, as seen in FIG. 7A, resulting inbetter coupling of sealing portion 722 to legs 720 and a more uniformcurling of sealing portion 722 in the formation of a sealing ring.

Although the elongated legs in all of the embodiments described abovehave a substantially linear configuration in the extended configuration,they may be formed with other configurations. FIG. 7B illustrates aheart valve 700B having nonlinear elongated legs. Heart valve 700Bextends between proximal end 702 and a distal end (not shown) andincludes stent 706 and a valve assembly having a cuff and leaflets asdescribed above. Heart valve 700B includes elongated legs 720B that arecurved or wavy in their extended configuration in contrast to thesubstantially linear legs of the previous embodiments. Wavy legs 720Bmay couple to stent 706 at proximal end 702 of heart valve 700B andextend away from the distal end thereof. Legs 720B may be formed to curlin their relaxed configuration in a manner similar to the elongated legsdescribed above. A sealing portion 722B may be attached to legs 720B soas to form a sealing ring in the relaxed configuration of the legs.

In FIGS. 7C and 7D, another example is shown in which heart valve 700Cextends between a proximal end 702 and a distal end (not shown) andincludes stent 706 and pairs of elongated legs 720C, 720D. Heart valve700C further includes a valve assembly having a cuff and leaflets and asealing portion (none of which are shown for the sake of clarity). Inthe extended configuration of the legs, shown in FIG. 7C, legs 720C,720D are formed in pairs that originate at a common attachment end 725at the apex of a cell at proximal end 702 and extend away from thedistal end of heart valve 700C in substantially linear configurations toterminate in independent free ends 726. As shown in their relaxedconfiguration in FIG. 7D, legs 720C, 720D may curl upward toward thedistal end of heart valve 700C along with the attached sealing portion,as previously described, to form a sealing ring. This configuration mayprovide additional structure for forming and supporting the sealingring.

As will be appreciated from the embodiments described above, theelongated legs may be attached at the proximal end of a heart valve oranywhere in the annulus portion of the valve. Additionally, in theirextended configuration, the elongated legs may extend either toward oraway from the distal end of the heart valve, and in their relaxedconfiguration, may curl in either direction. By varying the points ofattachment and the orientation of the elongated legs, sealing rings maybe formed at different locations along the valve. In some applications,damaged or calcified native valve leaflets may not be resected prior toimplantation of a prosthetic heart valve. The location of the sealingrings may be modified to accommodate the unresected native valveleaflets.

FIGS. 8A-8C illustrate heart valves 800A-C disposed within a nativevalve annulus adjacent unresected native leaflets 803. In FIG. 8A, heartvalve 800A includes sealing ring 850A at a proximal end thereof andconfigured to be disposed below native leaflets 803 (i.e., in asub-leaflet location). Sealing ring 850A may be at least partiallydisposed below native leaflets 803 and may contact the native leafletsto provide a seal between heart valve 800A and native leaflets 803. FIG.8B illustrates heart valve 800B having a sealing ring 850B spaceddistally of the proximal end of the valve and configured to be disposedwithin native leaflets 803 to provide a seal between heart valve 800Band native leaflets 803 (i.e., in an intra-leaflet location). FIG. 8Cillustrates a heart valve 800C having a sealing ring 850C spaced furtherdistally of the proximal end of the valve and configured to be disposedabove the free edges of native leaflets 803 to provide a seal betweenheart valve 800C and native leaflets 803 (i.e., in a supra-leafletlocation). Thus, sealing rings 850A-C may be disposed at variouslocations relative to native leaflets 803. It will be appreciated thatcombinations of any of these sealing rings may be possible. For example,a heart valve may include two sealing rings, a first sealing ring 850Aconfigured to be disposed below native leaflets 803, and a secondsealing ring 850C configured to be disposed above the free edges ofnative leaflets 803. When sealing ring 850A is disposed below the nativevalve leaflets 803 (FIG. 8A), it may prevent heart valve 800A frommigrating into the aorta. When sealing ring 850C is disposed above thenative valve leaflets (FIG. 8C), it may prevent heart valve 800C frommigrating into the left ventricle. Thus, with this and similarconfigurations, sealing rings may be used to anchor a heart valve in thenative valve annulus, thereby preventing the heart valve from migratingfrom its intended position.

FIGS. 9A and 9B illustrate a heart valve 900 pursuant to anotherembodiment having sealing features to mitigate perivalvular leakage.Heart valve 900 of FIG. 9A extends between a proximal end 902 and adistal end (not shown) and includes a stent 906, a valve assembly (notshown) including a cuff and leaflets, and elongated legs 920. Legs 920may be attached to stent 906 at attachment ends 925 near the proximalend 902 of heart valve 900 and, in the extended configuration of thelegs shown in FIG. 9A, may extend substantially linearly away from thedistal end of the valve, terminating in free ends 926. A sealing portion922 may be attached to legs 920 in the same manner as the sealingportions described above. When legs 920 of heart valve 900 return totheir relaxed configuration, instead of curling over themselves as shownin the previous embodiments, they may axially collapse to form anundulating shape, as seen in FIG. 9B. As a result of this collapse,portions of legs 920 may billow radially out from the profile of theannulus portion 940 of heart valve 900 by an additional distance d₁ toform distended portion 928. As shown in FIG. 9B, multiple distendedportions 928 may be formed. Each distended portion 928 may extendcircumferentially to form a sealing ring 929 or a portion of a sealingring.

FIG. 9C illustrates a first example of an elongated leg 920C that iscapable of collapsing axially to form distended portion 928. In thisfirst example, leg 920C may be substantially linear and have a firstlength L1 in an extended configuration. Leg 920C may be heat set orotherwise configured to axially collapse to an undulating shape 920C′having a shorter length L2 in the relaxed configuration. When leg 920Cassumes undulating shape 920C′ it will not only shorten, but will alsoform convex regions 930C along its length that collectively definedistended portions 928 of sealing ring 929. FIG. 9D illustrates anotherexample in which an elongated leg 920D having a length L1 in an extendedconfiguration shortens to an N-shape 920D′ having a length L3 in therelaxed configuration. Legs 920D form convex regions 930D along theirlengths that collectively define distended portions 928 of heart valve900. It will be understood that FIGS. 9C and 9D illustrate only twopossible examples for forming distended portions 928 and that varioustechniques and shapes may be used to alternate between a substantiallylinear elongated leg in the extended configuration and a shortened shapehaving convex regions in the relaxed configuration.

FIGS. 10A and 10B illustrate a heart valve 1000 in accordance withanother embodiment. Heart valve 1000 extends between proximal end 1002and distal end 1004, and may generally include stent 1006 and valveassembly 1008 having a plurality of leaflets 1010 and cuff 1012.Additionally, heart valve 1000 may include a number of elongated legs1020 and a sealing portion 1022 coupled to the elongated legs viaeyelets 1024 to mitigate perivalvular leakage. Legs 1020 may be formedof a shape memory material such as those described above with referenceto FIGS. 3A and 3B and may have an extended configuration and a relaxedconfiguration. Attachment ends 1025 of elongated legs 1020 may beaffixed to stent 1006 near proximal end 1002 of heart valve 1000, andlegs 1020 may extend away from the distal end 1004 of stent 1006 andterminate at eyelets 1024. In this example, sealing portion 1022 may bein the form of a generally toroidal-shaped sealing ring 1050, regardlessof whether legs 1020 are in their extended or relaxed configuration. Asused herein, the terms “toroid” and “toroidal” are not limited to acircle revolved about an axis external to the circle, which is parallelto the plane of the figure and does not intersect the figure, but alsoinclude the revolving of other plane geometrical figures such as, forexample, an oval, a triangle, a square and the like. Sealing ring 1050may be formed of a braided fabric comprising a plurality of braidedstrands, although it will be understood that any of the other materialsdescribed above with reference to FIGS. 3A and 3B may be used as well.In the extended configuration of legs 1020, sealing ring 1050 may bespaced away from proximal end 1002 by the length of the legs.

As noted above, legs 1020 may have an extended configuration and arelaxed configuration. FIG. 10B illustrates the relaxed configuration.When legs 1020 of heart valve 1000 are permitted to return to theirrelaxed configuration, they may curl up toward distal end 1004 and pullsealing ring 1050 over proximal end 1002 of heart valve 1000 so thatsealing ring 1050 is at least partially disposed over valve assembly1008 and/or cuff 1012. Sealing ring 1050 may have a radius larger thanthat of valve assembly 1008, the larger radius of sealing ring 1050being capable of filling any gaps between heart valve 1000 and thenative valve annulus (not shown). Thus, in this embodiment, sealing ring1050 is already formed in both the extended and relaxed configurationsof legs 1020, but is brought into place for sealing when legs 1020 curlupward in the relaxed configuration.

FIGS. 10C-E illustrate the extended configuration of legs 1020 and twoexamples of the relaxed configuration of legs 1020. As seen in FIG. 10C,in the extended configuration, legs 1020 are coupled to stent 1006 ofheart valve 1000 near proximal end 1002 and are substantially linearbetween eyelets 1024 and attachment ends 1025. In one example shown inFIG. 10D, elongated legs 1020 are configured to curl toward the distalend (not shown) of heart valve 1000, each elongated leg 1020 being bentstraight back so that substantially the entire leg lies in a singleplane Z. Alternatively, as shown in FIG. 10E, each elongated leg 1020may also be bent with respect to the plane of attachment Z such that itends in a second plane Z′ which forms an angle α with respect to planeof attachment Z. The angle between the two planes may be between about 1degree and about 60 degrees. By bending leg 1020 in such a manner, leg1020 may be more conformable, aiding in the transition between theextended and the relaxed configurations.

FIG. 10F is an enlarged partial perspective view showing the bending ofthe elongated legs of heart valve 1000F. Heart valve 1000F may extendbetween a proximal end 1002F and a distal end (not shown) and includesstent 1006F and elongated legs 1020F, each having an eyelet 1024F.Elongated legs 1020F may be coupled to stent 1006F at attachment ends1025F. It may be difficult to bend elongated legs 1020F due to thethickness and width of the legs. Elongated legs 1020F therefore may betwisted along their longitudinal axes in order to more easily bend thelegs. In addition to twisting, elongated legs 1020F may be bent asdescribed above with reference to FIG. 10E. The twisting and bending ofelongated legs 1020 may weaken the legs so that a desired stiffness isachieved for proper extension and relaxation of the legs.

FIGS. 11A-F are highly schematic partial side views of heart valves,showing variations in how the elongated legs are bent in the relaxedconfiguration. In a first example, heart valve 1100A includes stent 1106and elongated legs 1120A coupled thereto (FIG. 11A). Elongated legs1120A of heart valve 1100A bend in the shape of a semicircle, andsealing portion 1122A, which is attached to elongated legs 1120A, curlswith the elongated legs to form a sealing ring 1150A in the shape of asemicircle revolved about an axis external to the semicircle, which isparallel to the plane of the figure and does not intersect the figure.In a second example, heart valve 1100B includes stent 1106 and elongatedlegs 1120B coupled thereto (FIG. 11B). Elongated legs 1120B of heartvalve 1100B bend to form an almost complete circle, and sealing portion1122B, which is attached to elongated legs 1120B, curls with theelongated legs to form a sealing ring 1150B in the shape of an ellipsoidrevolved in the manner described above. FIG. 11C illustrates anotherexample in which heart valve 1100C includes stent 1106 and elongatedlegs 1120C, which bend in multiple curls to form sealing portion 1122Cinto a spiral-shaped sealing ring 1150C in the shape of a revolved curl.It will be understood from these examples that the elongated legs mayinclude any number of curls or portions of curls.

Moreover, the elongated legs may take a number of shapes other thancurls. For example, in FIG. 11D, heart valve 1100D includes elongatedlegs 1120D coupled to stent 1106. Elongated legs 1120D are configured tobend in the shape of a triangle as shown, sealing portion 1122D bendingwith them to form sealing ring 1150D in the shape of a revolvedtriangle. FIG. 11E illustrates another example of heart valve 1100Ehaving elongated legs 1120E coupled to stent 1106. Elongated legs 1120Ecurl in a substantially elliptical shape having a major axis m1 disposedat an upward angle β1 with respect to an axis x extending in the radialdirection of heart valve 1100E. In this example, major axis m1 forms anupward angle β1 of about 40 degrees with respect to axis x, causingsealing portion 1122E to form sealing ring 1150E in the shape of adistally-pointing revolved ellipsoid. In an alternative configuration,elongated legs 1120F may be coupled to stent 1106 of heart valve 1100Fas shown in FIG. 11F. Elongated legs 1120F curl in a substantiallyelliptical shape as in FIG. 11E, the ellipse having a major axis m2disposed at a downward angle β2 with respect to an axis x extending inthe radial direction of heart valve 1100F. In this example, major axism2 forms a downward angle β2 of about 40 degrees with respect to axis x,causing sealing portion 1122F to form sealing ring 1150F in the shape ofa proximally-pointing revolved ellipsoid. It will be understood thatvarious modifications may be made to any of these basic shapes of theelongated legs. For example, the foregoing shapes may be inverted whenthe elongated legs extend toward the distal end of a heart valve (e.g.,a triangle that is inverted from that shown in FIG. 11D). Thus, theelongated legs may take any desired shape to form sealing rings ofvarious profiles and radiuses to adequately seal the region between theheart valve and the native valve annulus.

FIG. 12 is a highly schematic cross-sectional view showing heart valve1200 having stent 1202, valve assembly 1204 including a cuff (not shown)and leaflets 1208, and elongated legs 1250 supporting a sealing portion1260. Legs 1250 have curled up to form sealing ring 1270 and heart valve1200 has been disposed within native valve annulus 1280. As seen in FIG.12, sealing ring 1270 has radially expanded to fill gaps 200 shown inFIG. 2, and may be capable of promoting tissue growth between heartvalve 1200 and native valve annulus 1280. For example, sealing portion1260 may be innately capable of promoting tissue growth and/or may betreated with a biological or chemical agent to promote tissue growth,further enabling sealing ring 1270, when expanded, to seal the heartvalve within the native valve annulus. Alternatively, the expandedsealing ring 1270 may be sufficiently dense to adequately seal aroundheart valve 1200 without the need for major tissue growth. Sealingportion 1260 may also be double-layered and in embodiments having a meshsealing portion, it may include tighter braiding to more completelyocclude the space between heart valve 1200 and native valve annulus1280. When sealing ring 1270 is functioning properly, heart valve 1200will be adequately sealed within native valve annulus 1280 so that bloodflows through leaflets 1208 of valve assembly 1204, and so that bloodflow through any gaps formed between heart valve 1200 and native valveannulus 1280 is limited or reduced.

FIGS. 13A-C illustrate a heart valve 1300 in accordance with anotherembodiment. Heart valve 1300 extends between proximal end 1302 anddistal end 1304, and may generally include stent 1306 formed of aplurality of struts 1307, and valve assembly 1308 having a plurality ofleaflets 1310 and a cuff 1312. Cuff 1312 may include surplus portion1322 that extends past the most-proximal struts 1307 of stent 1306. Insome examples, surplus portion 1322 may longitudinally extend betweenabout 10 mm and about 20 mm proximally from the most-proximal struts1307 of stent 1306. Surplus portion 1322 may be formed of the samematerial as the rest of cuff 1312 and may be formed integrally therewithfrom a single piece of material. Alternatively, surplus portion 1322 maybe formed of a different material than cuff 1312 that is sutured, gluedor otherwise affixed to the proximal end of cuff 1312.

FIG. 13B illustrates heart valve 1300 after surplus portion 1322 hasbeen rolled to form sealing ring 1350A. After assembly of cuff 1312 tostent 1306, surplus portion 1322 may be rolled in the direction ofdistal end 1304 until it is aligned with the proximal-most struts 1307to form sealing ring 1350A. In this example, surplus portion 1322 isrolled into a generally toroidal-shaped sealing ring 1350A near proximalend 1302 of heart valve 1300 (e.g., at a subannular position). Sealingring 1350A may be formed of one complete revolution of surplus portion1322, or of a series of revolutions (e.g., two, three or morerevolutions of surplus portion 1322).

Sealing ring 1350A may maintain its shape through a variety of methods,such as by being tied to select struts 1307 of stent 1306. In oneexample, as seen in the enlarged schematic view of FIG. 13B, end struts1360 a and 1360 b of stent 1306 meet to form a horseshoe-shaped end 1370having a partial slot 1372 therebetween. A number of locking stitchesLS1 may be tied around horseshoe-shaped ends 1370, and specificallyaround each slot 1372 and sealing ring 1350A to keep the sealing ringfrom unfurling. Locking stitches LS1 may be formed of a suture, stringor any other suitable biocompatible thread. It will be understood that,though three locking stitches are shown around the circumference of theheart valve to couple sealing ring 1350A to stent 1306, any number oflocking stitches may be used. Other techniques for maintaining the shapeof sealing ring 1350A may also be used including adhesive, glue or thelike. Sealing ring 1350A may have a radius larger than that of valveassembly 1308, the larger radius of sealing ring 1350A being capable offilling any gaps between heart valve 1300 and the native valve annulus(not shown).

FIG. 13C illustrates prosthetic heart valve 1300 in native valve annulus1380 after formation of sealing ring 1350A as seen from proximal end1302 (e.g., as seen from the annulus end toward the aortic end of theheart valve). Sealing ring 1350A has been secured to stent 1306 via aseries of locking stitches LS1. The outer diameter of stent 1306 at theproximal end is indicated with a dashed-line. Sealing ring 1350A extendsradially outward from the outer diameter of stent 1306 at the proximalend of heart valve 1300 by a radial distance r1. In at least someexamples, radial distance r1 may be between about 1 mm and about 2.5 mm.

FIG. 13D illustrates heart valve 1300D, which is a variant of heartvalve 1300 of FIGS. 13A-C. Heart valve 1300D extends between proximalend 1302 and distal end 1304, and may generally include stent 1306formed of struts 1307, and valve assembly 1308 having a plurality ofleaflets 1310 and a cuff 1312. A surplus portion 1322D of cuff 1312 hasbeen rolled to form sealing ring 1350D in a manner similar to thatdescribed above, except that sealing ring 1350D has been rolled to aposition closer to distal end 1304 and leaflets 1310 than sealing ring1350A (e.g., at an intra-annular position). After rolling surplusportion 1322D and forming sealing ring 1350D at the appropriateposition, locking stitches LS2 may be coupled to sealing ring 1350D andselect struts 1307 of stent 1306 to secure the sealing ring in place.

FIGS. 14A-B illustrates a heart valve 1400 in accordance with anotherembodiment. Heart valve 1400 extends between proximal end 1402 anddistal end 1404, and may generally include stent 1406 formed of struts1407, and valve assembly 1408 having a plurality of leaflets 1410 and acuff 1412. Cuff 1412 may include a surplus portion 1422 that extendsproximally past the most-proximal struts 1407 of stent 1406. In someexamples, surplus portion 1422 may extend between about 5 mm and about20 mm from the most-proximal struts 1407 of stent 1406. Surplus portion1422 may be formed of the same material as the rest of cuff 1412 and maybe integrally formed therewith of a single piece of material.

In this example, surplus portion 1422 is formed of a thickened materialthat is configured to circumferentially buckle in an accordion-likefashion at certain locations to form undulating sealing ring 1450 whenheart valve 1400 is released from a delivery device. Undulating sealingring 1450 allows for more surface area to fill in and around voids.Furthermore, undulating sealing ring 1450 is capable of being folded inan organized manner for loading and delivery. Terminal sutures TS1 mayattach portions of surplus portion 1422 to selected struts 1407 to aidin the formation of undulating ring 1450. In some examples, sutures TS1are the same sutured that are used to attach cuff 1412 to the struts1407 so that no extra steps or bulk is added. Undulating ring 1450 isannularly disposed around proximal end 1402 of heart valve 1400.Undulating ring 1450 alternates between a series of peaks 1460 andvalleys 1470 and radially expands to a diameter greater than thediameter of the proximal end of stent 1406. Undulating ring 1450 mayinclude thin porcine pericardial tissue about between about 0.005 inchesand about 0.007 inches in thickness or UHMWPE or PET fabric betweenabout 0.003 inches and about 0.005 inches in thickness.

FIG. 14B illustrates prosthetic heart valve 1400 in native valve annulus1480 after formation of undulating sealing ring 1450, as seen fromproximal end 1402 (e.g., as seen from the annulus end toward the aorticend of the heart valve). Surplus portion 1422 has buckled to formundulating sealing ring 1450. The outer diameter of stent 1406 at theproximal end is indicated with a dashed-line. Undulating ring 1450extends radially outward from the outer diameter of stent 1406 at theproximal end of heart valve 1400 by a radial distance r2. In at leastsome examples, radial distance r2 may be between about 1.0 mm and about10.0 mm Radial distance r2 may also be between about 1.0 mm and about2.5 mm.

In another variation (FIGS. 15A and 15B), heart valve 1500 extendsbetween proximal end 1502 and distal end 1504, and may generally includestent 1506 formed of struts 1507, and valve assembly 1508 having aplurality of leaflets 1510 and a cuff 1512. Cuff 1512 may include anextended surplus portion 1522 that extends proximally past themost-proximal struts 1507 of stent 1506. In some examples, surplusportion 1522 may extend between about 5.0 mm and about 10.0 mm from themost-proximal struts 1507 of stent 1506. Surplus portion 1522 may beformed of the same material as the rest of cuff 1512 and may beintegrally formed therewith of a single piece of material.

In this example, surplus portion 1522 deploys into a flat sealing halo1550, which flares radially outward to a diameter greater than thediameter of the proximal end of stent 1506. FIG. 15B illustratesprosthetic heart valve 1500 in native value annulus 1580 after formationof sealing halo 1550, as seen from proximal end 1502 (e.g., as seen fromthe annulus end toward the aortic end of the heart valve. The outerdiameter of stent 1506 at the proximal end is indicated with adashed-line. Sealing halo 1550 extends radially outward from the outerdiameter of stent 1506 at the proximal end of heart valve 1500 by aradial distance r3. In at least some examples, radial distance r3 isbetween about 2 mm and about 10 mm.

In another variation (FIGS. 16A and 16B), heart valve 1600 extendsbetween proximal end 1602 and distal end 1604, and may generally includestent 1606 formed of struts 1607, and valve assembly 1608 having aplurality of leaflets 1610 and a cuff 1612. Cuff 1612 may include anextended surplus portion 1622 that extends proximally past themost-proximal struts 1607 of stent 1606. In some examples, surplusportion 1622 may extend between about 2 mm and about 10.0 mm from themost-proximal struts 1607 of stent 1606. Surplus portion 1622 may beformed of the same material as the rest of cuff 1612 and may beintegrally formed therewith of a single piece of material.

In this example, surplus portion 1622 forms sealing body 1650 having anumber of independently moveable limbs 1660, which flare out radially.FIG. 16B illustrates prosthetic heart valve 1600 in native valve annulus1680, as seen from proximal end 1602 (e.g., as seen from the annulus endtoward the aortic end of the heart valve). Surplus portion 1622 hasflared radially outward to form sealing body 1650 and limbs 1660 havealso spread apart. The outer diameter of stent 1606 at the proximal endis indicated with a dashed-line. Sealing body 1650 extends radiallyoutward from the outer diameter of stent 1606 at the proximal end ofheart valve 1600 by a minimum radial distance of at least r4. In atleast some examples, radial distance r4 is between about 2.0 mm andabout 10.0 mm.

While the inventions herein have been described for use in connectionwith heart valve stents having a particular shape, the stent could havedifferent shapes, such as a flared or conical annulus section, aless-bulbous aortic section, and the like, as well as a differentlyshaped transition section. The sealing rings described may also have acircular, D-shaped or elliptical cross-section. Additionally, though thesealing structures have been described in connection with expandabletranscatheter aortic valve replacement, they may also be used inconnection with other expandable cardiac valves, as well as withsurgical valves, sutureless valves and other devices in which it isdesirable to create a seal between the periphery of the device and theadjacent body tissue.

In some embodiments, a prosthetic heart valve for replacing a nativevalve includes a collapsible and expandable stent having a proximal endand a distal end and a valve assembly disposed within the stent, thevalve assembly including a plurality of leaflets. The heart valvefurther includes a cuff annularly disposed about the stent and having asurplus portion capable of forming a sealing structure at the proximalend of the stent, the sealing structure having a deployed condition witha diameter in the deployed condition greater than a diameter of theproximal end of the stent.

In some examples, the surplus portion may include at least one of ametallic mesh, a shape-memory material, a polymeric material or a tissuematerial. The sealing structure may include a toroid formed by rollingthe surplus portion upon itself. The stent may include horseshoe-shapedends and the toroid is coupled to at least some of the horseshoe-shapedends via a plurality of locking sutures. The plurality of lockingsutures may include three locking sutures. The stent may include anannulus section and the toroid may be disposed proximal to the annulussection of the stent. The stent may include an annulus section and thetoroid may be disposed about the annulus section of the stent. Thesealing structure may include an undulating sealing ring having aplurality of alternating peaks and valleys. The stent may include aplurality of struts and the surplus portion is coupled to selected onesof the struts via terminal sutures to enable circumferential buckling ofthe surplus portion into the undulating sealing ring. The sealingstructure may include a flat sealing halo. The sealing structure mayinclude a body having a plurality of independently moveable limbs. Thediameter of the sealing structure in the deployed condition may have adiameter greater than the diameter of the proximal end of the stent bybetween about 2.0 mm and about 10.0 mm.

In some embodiments, a prosthetic heart valve for replacing a nativevalve includes a collapsible and expandable stent having a proximal endand a distal end, a valve assembly disposed within the stent, the valveassembly including a plurality of leaflets and a cuff annularly disposedabout the stent and having an attached end coupled to the stent and afree end extending past the proximal end of the strut and capable offorming a sealing structure for sealing gaps between the prostheticheart valve and a native valve annulus.

In some examples, a free end is configured to roll upon itself to createa toroid. The free end may be configured to flare out radially to form aflattened halo adjacent the proximal end of the stent. The free end mayinclude a body having a plurality of independently moveable limbs.

In some embodiments, a method of making a prosthetic heart valve forreplacing a native valve includes providing a collapsible and expandablestent having a proximal end and a distal end, coupling a valve assemblyto the stent, the valve assembly including a plurality of leaflets,coupling a cuff to the stent so that a surplus portion of the cuffextends beyond the proximal end of the strut and converting the surplusportion of the cuff into a sealing structure at the proximal end of thestent, the sealing structure having a diameter greater than a diameterof the proximal end of the stent.

In some examples, a converting step includes rolling the surplus portionof the cuff into a toroid shape. The method may further include securingthe surplus portion to the stent via at least one suture to maintain thetoroid shape.

It will be appreciated that the various dependent claims and thefeatures set forth therein can be combined in different ways thanpresented in the initial claims. It will also be appreciated that thefeatures described in connection with individual embodiments may beshared with others of the described embodiments.

1. A prosthetic heart valve for replacing a native valve, comprising: acollapsible and expandable stent having a proximal end, a distal end,and a plurality of struts forming rows of cells, the stent in a deployedcondition having a first diameter adjacent the proximal end, and asecond diameter adjacent the distal end, the second diameter beinggreater than the first diameter; and a valve assembly disposed withinthe stent, the valve assembly including: a plurality of leaflets, eachleaflet having an attached edge and a free edge; and a cuff annularlydisposed on a surface of the stent to cover at least one row of cells,and having an attached end coupled to the stent at a location distal tothe attached edges of the plurality of leaflets, and a free end rolledover itself at least one full revolution toward the distal end to form asealing ring for sealing gaps between the prosthetic heart valve and anative valve annulus, the sealing ring having an outer sealing diameterthat is greater than the first diameter, but smaller than the seconddiameter.
 2. The prosthetic heart valve of claim 1, wherein the stentincludes elongated legs extending away from the distal end of the stentand coupled to the sealing ring.
 3. The prosthetic heart valve of claim1, wherein the legs are curled in the sealing ring in the at least onefull revolution along with the free end of the cuff.
 4. The prostheticheart valve of claim 1, wherein the sealing ring includes at least oneof a metallic mesh, a shape-memory material, a polymeric material or atissue material.
 5. The prosthetic heart valve of claim 1, wherein thesealing ring comprises a toroid.
 6. The prosthetic heart valve of claim5, wherein the stent includes an annulus section and the toroid isdisposed proximal to the annulus section of the stent.
 7. The prostheticheart valve of claim 1, wherein the outer sealing diameter of thesealing ring in the deployed condition is greater than the firstdiameter by between about 2.0 mm and about 10.0 mm.
 8. A prostheticheart valve for replacing a native valve, comprising: a collapsible andexpandable stent having a proximal end, a distal end, and a plurality ofstruts forming rows of cells; and a valve assembly disposed within thestent, the valve assembly including: a plurality of leaflets, eachleaflet having an attached edge and a free edge; and a cuff annularlydisposed on a surface of the stent to cover at least one row of cells,and having an attached end coupled to the stent at a location distal tothe attached edges of the plurality of leaflets, the cuff in a collapsedcondition having a free end extending past the proximal end of the stentand having a memory bias such that the free end is configured to rollover itself at least one full revolution toward the distal end to form asealing ring for sealing gaps between the prosthetic heart valve and anative valve annulus.
 9. The prosthetic heart valve of claim 8, whereinthe stent includes elongated legs extending away from the distal end ofthe stent and coupled to the sealing ring.
 10. The prosthetic heartvalve of claim 8, wherein the sealing ring includes at least one of ametallic mesh, a shape-memory material, a polymeric material or a tissuematerial.
 11. The prosthetic heart valve of claim 8, wherein the sealingring comprises a toroid.
 12. The prosthetic heart valve of claim 11,wherein the stent includes an annulus section and the toroid is disposedproximal to the annulus section of the stent.
 13. The prosthetic heartvalve of claim 8, wherein the outer sealing diameter of the sealing ringin the deployed condition is greater than the first diameter by betweenabout 2.0 mm and about 10.0 mm.
 14. A prosthetic heart valve forreplacing a native valve, comprising: a collapsible and expandable stenthaving a proximal end, a distal end, and a plurality of struts formingrows of cells, the stent being movable between collapsed and deployedconditions; the stent in a deployed condition having a first diameteradjacent the proximal end, and a second diameter adjacent the distalend, the second diameter being greater than the first diameter; and avalve assembly disposed within the stent, the valve assembly including:a plurality of leaflets, each leaflet having an attached edge and a freeedge; and a cuff annularly disposed on a surface of the stent to coverat least one row of cells, and having an attached end coupled to thestent at a location distal to the attached edges of the plurality ofleaflets, the cuff in the collapsed condition of the stent having a freeend extending past the proximal end of the stent and having a memorybias such that the free end is configured to roll over itself, and thecuff in the deployed condition of the stent having the free end rolledover itself at least one full revolution toward the distal end to form asealing ring for sealing gaps between the prosthetic heart valve and anative valve annulus, the sealing ring having an outer sealing diameterthat is greater than the first diameter, but smaller than the seconddiameter.
 15. The prosthetic heart valve of claim 14, wherein the stentincludes elongated legs extending away from the distal end of the stentand coupled to the sealing ring.
 16. The prosthetic heart valve of claim15, wherein the legs are movable between an extended configuration and arelaxed configuration, the legs having the extended configuration in thecollapsed condition of the stent, the legs having the relaxedconfiguration in the deployed condition of the stent in which the legsare curled in the sealing ring in the at least one full revolution alongwith the free end of the cuff.
 17. The prosthetic heart valve of claim14, wherein the sealing ring includes at least one of a metallic mesh, ashape-memory material, a polymeric material or a tissue material. 18.The prosthetic heart valve of claim 14, wherein the sealing ringcomprises a toroid with the cuff in the deployed condition.
 19. Theprosthetic heart valve of claim 18, wherein the stent includes anannulus section and the toroid is disposed proximal to the annulussection of the stent.
 20. The prosthetic heart valve of claim 14,wherein the outer sealing diameter of the sealing ring in the deployedcondition is greater than the first diameter by between about 2.0 mm andabout 10.0 mm.